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algae proving rather unexpectedly infrequent, especially on the 

 Pacific shores of the Isthmus, there was considerable opportunity 

 for turning attention to the land flora, particularly the fungi, 

 Hepaticae, Musci, etc., and for securing photographs of general 

 botanical interest. The speaker exhibited many specimens and 

 also numerous photographs, illustrating the floral aspects of the 

 region and details of certain selected plants. A marine flora, in 

 the more popular sense of the word, seems to be almost non- 

 existent in the Bay of Panama, or at least in the parts of it that 

 were examined. There are, however, a few closely incrusting 

 species of such genera as Ralfsia and Hildenbrandtia and of the 

 families Squamariaceae and Corallinaceae, and there are repre- 

 tatives of the Cyanophyceae and of such genera as Enterornorpka, 

 ChaetomorpJia, Bostrychia, Caloglossa, Catenella, LophosipJwnia, 

 Herposiphonia, and a few other rather small and inconspicuous 

 kinds. Not a fragment of an alga or of any marine seed-plant 

 was found washed ashore at any part of the Bay of Panama that 

 was examined. The cause of the paucity of marine plant life in 

 this region is not wholly obvious, but is probably to be found in 

 the combination of wide-ranging tides with tropical conditions as 

 to hght and heat. The scorching effect of the direct rays of the 

 tropical sun is of course unfavorable to any luxuriant develop- 

 ment of the algae between the tide-lines, and at and below the 

 low-water mark the fluctuations in water-pressure and light- 

 intensity seem here in some way to act unfavorably upon plant- 

 life. At least, on the Atlantic or Caribbean side of the Isthmus, 

 only fifty miles to the northward, where the conditions are appar- 

 ently similar except that the tides are much lighter, there is a 

 fairly well-developed and diversified marine flora, in striking con- 

 trast to that of the Bay of Panama. On the Pacific side, in the 

 Bay of Panama, the tides have a maximum vertical range of from 

 ten to nineteen feet ; at Colon, on the Atlantic or Caribbean side, 

 the range is commonly less than two feet. About three weeks 

 were devoted to making collections at Colon and vicinity, with 

 more satisfactory results so far as the algae were concerned. A 

 more detailed account of the expedition appears in the Journal of 

 the Nezv York Botanical Garden for February. 



